<?hh <<__EntryPoint>> function main(): void {
date_default_timezone_set("UTC");
$tm = strtotime("2005-01-01 01:01:01");
echo date(DATE_ISO8601, strtotime('+5days', $tm));
echo "\n";
echo date(DATE_ISO8601, strtotime('+1month', $tm));
echo "\n";
echo date(DATE_ISO8601, strtotime('+1year', $tm));
echo "\n";
echo date(DATE_ISO8601, strtotime('+5 days', $tm));
echo "\n";
echo date(DATE_ISO8601, strtotime('+1 month', $tm));
echo "\n";
echo date(DATE_ISO8601, strtotime('+1 year', $tm));
echo "\n";
}
